Jazz's Ancestors and the AFM

This caught my eye right away in the table of contents for the April 2008 International Musician, the monthly newspaper of the music union, the American Federation of Musicians (AFM). Describing a cover story on pianist Joe Sample:

"Joe Sample...always comes back to his roots...his love of jazz's ancestors - soul, gospel and R&B."

Whaa? I must have missed that day in Jazz 101 talking about R&B being an ancestor of jazz. I can't believe no one at the music union caught that.